Promising a sporting legacy, with more people taking part in activities at grass-roots level, was at the heart of the London 2012 bid. But research conducted at the University of Kent into the legacy left by the 2004 Athens Olympics found there was at best only a temporary impact on people taking up sport.
Dr Sakis Pappous, of the Centre for Sport Studies, said there was only a short-lived boost in sports activity in Greece between 2003 and 2004 of 6 per cent.
Five years on from the Games, the number of people who said they exercised regularly had fallen by 13 per cent.
Dr Pappous said: "It is not even clear that the short-lived increase in those exercising regularly was down to the Games effect, as Greece won the Uefa European football championship in that year, which may have influenced sports participation.
"Rather than producing a lasting impact on a generation of people who are excited about sport, the Games in Greece had at best only a temporary impact on participation in sport and physical activity.
"The data for the Greek population suggests that, if a broader strategy towards an active lifestyle is not implemented, then sporting excitement on its own will not sustain participation.
"In fact, there may be a reduction and possibly a rebound effect, where participation drops to levels lower even than during the pre-Olympic period."
In November, a 135 million Lottery-funded drive was announced in Britain to encourage mass participation in sport on the back of the London Games.
Olympics minister Hugh Robertson has said tackling the poor state of sports facilities across the country is a top priority.
A nationwide campaign to offer teenagers and young adults six weeks of coaching in the sport of their choice was also announced.